Question

Que: Gold crystalises in ccp structure. The total number of voids present in 197 g of gold will be [Au=197]

Answer 1

8 tetrahedral and 4 octahedral voids are present.

Answer 2

no.of atoms in one fcc unit cell= 4

no of voids present(octahedral voids+ tetrahedral voids)=2n+n=3n

(where n=number of atoms)

total number of voids present=12

for one atom no.of voids =12/4=3

for 197 grams of gold 3Na